Millcreek Canyon starts at the Power Dam & you can hike up. The actual water hole is often quote as being called "Left Hand" by us locals and has been a favorite. Growing up, I remember spending a whole summer hiking up every single day to jump off the rocks into the water hole (Disclaimer: many people have been injured here and we do not suggest nor will give any suggestions on how/where to jump). The waterfall has been sanded in spot to also aid in being able to climb back up (Second Disclaimer: Be very careful in climbing up this as it can take quite a bit of athleticism and we have seem multiple slip down the waterfall). Overall, this is an amazing place to hang out and cool off during the hot temperature time of the year in Moab. During the early spring, even thought the temperature is warm in Moab the water can actually be really cold due to it being the run off from the La Sal Mountains.
The Mill Creek trail begins at the trailhead parking area's northeast end. (See the map below for directions.) Ignore any trails going left toward the creek and continue east on the wide dirt route.
Arrive at the base of a tiny waterfall at the site of an ancient power station after around 800-ft. Bypass the falls on the right (south), climbing over the cement block dam on a slick rock ledge and then walking along a narrow slickrock shelf alongside the creek. The traction along the angled shelf may be an issue for some. Wade in the creek if this is the case.